Eleventh chord

In music theory, an eleventh chord is a chord that contains the tertian extension of the eleventh. Typically found in jazz, an eleventh chord also usually includes the seventh and ninth, and elements of the basic triad structure. Variants include the dominant eleventh, minor eleventh, and the major eleventh chord. Symbols include: Caug11, C9(aug11), C9(+11), C9alt11, Cmin9(11), C-(9)(11). The eleventh in an eleventh chord is, "almost always sharpened, especially in jazz," at least in reference to the third, with CM11 (major eleventh): C-E-G-B-D-F♯, Cm11 (minor eleventh): C-E♭-G-B♭-D-F, and C11 (dominant eleventh): C-E-G-B♭-D-F.

However, since the major diatonic eleventh would create a dissonant minor ninth interval with the third of the chord, including the third is a rare phenomenon, even in 20th-century classical music. Though rare, in rock and popular music, for example 52 seconds into "Sun King" on the Beatles' Abbey Road, the third of the dominant eleventh ("as theoretically conceived": C, E, G, B♭, D, F  play ), for example, is usually omitted. It may be notated in charts as, C11, or, more often, "descriptively," as Gm7/C. The fifth is also sometimes omitted, thus turning the chord into a suspended chord (C, B♭, D, F).

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